The present invention is directed to recording sheets, such as transparency materials, filled plastics, papers, and the like. More specifically, the present invention is directed to recording sheets particularly suitable for use in ink jet printing processes. One embodiment of the present invention is directed to a printing process which comprises (a) providing a recording sheet which comprises a substrate, at least one monomeric salt, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler; (b) applying an aqueous recording liquid to the recording sheet in an imagewise pattern; and (c) thereafter exposing the substrate to microwave radiation, thereby drying the recording liquid on the recording sheet.
Recording sheets suitable for use in ink jet printing are known. For example, U.S. Pat. No. 4,740,420 (Akutsu et al.) discloses a recording medium for ink jet printing comprising a support material containing at least in the surface portion thereof a water soluble metal salt with the ion valence of the metal thereof being 2 to 4 and a cationic organic material. The cationic organic materials include salts of alkylamines, quaternary ammonium salts, polyamines, and basic latexes.
U.S. Pat. No. 4,576,867 (Miyamoto) discloses an ink jet recording paper with improved water resistance and sunlight fastness of the image formed on the paper wherein the recording paper has attached to its surface a cationic resin of the formula ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 represent alkyl groups, m represents a number of 1 to 7, and n represents a number of 2 to 20, and Y represents an acid residue.
U.S. Pat. No. 4,446,174 (Maekawa et al.) discloses an ink jet recording method for producing a recorded image on an image receiving sheet with a jet of aqueous ink, wherein an ink jet is projected onto an image receiving sheet comprising a surface layer containing a pigment, and wherein the surface layer is capable of adsorbing a coloring component in the aqueous ink. Poly (vinyl benzyl trimethyl ammonium chloride), poly (diallyl dimethyl ammonium chloride), and poly (methacryloxyethyl-.beta.-hydroxyethyl dimethyl ammonium chloride) are disclosed as dye absorbing adhesive materials.
U.S. Pat. No. 4,830,911 (Kojima et al.) discloses a recording sheet for ink jet printers which gives an image by the use of an aqueous ink containing a water-soluble dye, coated or impregnated with either of or a mixture of two kinds of water soluble polymers, one whose polymeric unit is alkylquaternaryammonium (meth)acrylate and the other whose polymer unit is alkylquaternaryammonium (meth)acrylamide, wherein the water soluble polymers contain not less than 50 mol percent of a monomer represented by the formula ##STR2## where R represents hydrogen or methyl group, n is an interger from 1 to 3 inclusive, R.sub.1, R.sub.2, and R.sub.3 represent hydrogen or the same or different aliphatic alkyl group with 1 to 4 carbon atoms, X represents an anion such as a halogen ion, sulfate ion, alkyl sulfate ion, alkyl sulfonate ion, aryl sulfonate ion, and acetate ion, and Y represents oxygen or imino group.
U.S. Pat. No. 4,554,181 (Cousin et al.) discloses an ink jet recording sheet having a recording surface which includes a combination of a water soluble polyvalent metal salt and a cationic polymer, the polymer having cationic groups which are available in the recording surface for insolubilizing an anionic dye.
U.S. Pat. No. 4,877,680 (Sakaki et al.) discloses a recording medium comprising a substrate and a nonporous ink receiving layer. The ink receiving layer contains a water-insoluble polymer containing a cationic resin. The recording medium may be employed for recording by attaching droplets of a recording liquid thereon.
European Patent Publication 0 439 363 A1, published Jul. 31, 1991, corresponding to U.S. Pat. No. 5,302,249, the disclosure of which is totally incorporated herein by reference, discloses a paper which comprises a supporting substrate with a coating comprising (a) a desizing component selected from the group consisting of (1) hydrophilic poly(dialkylsiloxanes); (2) poly(alkylene glycol); (3) poly(propylene oxide)-poly(ethylene oxide) copolymers; (4) fatty ester modified compounds of phosphate, sorbitan, glycerol, poly(ethylene glycol), sulfosuccinic acid, sulfonic acid and alkyl amine; (5) poly(oxyalkylene) modified compounds of sorbitan esters, fatty amines, alkanol amides, castor oil, fatty acids and fatty alcohols; (6) quaternary alkosulfate compounds; (7) fatty imidazolines; and mixtures thereof, and (b) a hydrophilic binder polymer. The binder polymer may be a quaternary ammonium copolymer such as Mirapol WT, Mirapol AD-1, Mirapol AZ-1, Mirapol A-15, Mirapol-9, Merquat-100, or Merquat-550, available from Miranol Incorporated.
U.S. Pat. No. 5,223,338 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a coating consisting essentially of (1) quaternary ammonium polymers selected from the group consisting of (a) polymers of Formula I ##STR3## wherein n is an integer of from 1 to about 200, R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are each independently selected from the group consisting of alkyl groups, hydroxyalkyl groups, and polyoxyalkylene groups, p is an integer of from 1 to about 10, q is an integer of from 1 to about 10, X is an anion, and Y.sub.1 is selected from the group consisting of --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --, --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --, --(CH.sub.2).sub.k --, wherein k is an integer of from about 2 to about 10, and --CH.sub.2 CH(OH)CH.sub.2- ; (b) polymers of Formula II ##STR4## wherein wherein n is an integer of from 1 to about 200, R.sub.5, R.sub.6, R.sub.7, and R.sub.8 are each independently selected from the group consisting of alkyl groups, hydroxyalkyl groups, and polyoxyalkylene groups, m is an integer of from 0 to about 40, r is an integer of from 1 to about 10, s is an integer of from 1 to about 10, X is an anion, and Y.sub.2 is selected from the group consisting of --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --, --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --, --(CH.sub.2).sub.k --, wherein k is an integer of from about 2 to about 10, and --CH.sub.2 CH(OH)CH.sub.2 --; (c) copolymers of Formula III ##STR5## wherein a and b are each integers wherein the sum of a +b is from about 2 to about 200, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, and R.sub.8 are each independently selected from the group consisting of alkyl groups, hydroxyalkyl groups, and polyoxyalkylene groups, p is an integer of from 1 to about 10, q is an integer of from 1 to about 10, X is an anion, and Y.sub.1 and Y.sub.2 are each independently selected from the group consisting of --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --, --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --, --(CH.sub.2).sub.k --, wherein k is an integer of from about 2 to about 10, and --CH.sub.2 CH(OH)CH.sub.2 --; (d) mixtures of polymers of Formula I and polymers of Formula II; (e) mixtures of polymers of Formula I and copolymers of Formula III; (f) mixtures of polymers of Formula II and copolymers of Formula III; and (g) mixture of polymers of Formula I, polymers of Formula II, and copolymers of Formula III; (2) an optional binder polymer; and (3) an optional filler.
U.S. Pat. No. 5,212,008 (Malhotra et al.), the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate; a first coating in contact with the substrate which comprises a crosslinking agent selected from the group consisting of hexamethoxymethyl melamine, methylated melamine-formaldehyde, methylated urea-formaldehyde, cationic urea-formaldehyde, cationic polyamine-epichlorohydrin, glyoxal-urea resin, poly (aziridine), poly (acrylamide), poly (N,N-dimethyl acrylamide), acrylamide-acrylic acid copolymer, poly (2-acrylamido-2-methyl propane sulfonic acid), poly (N,N-dimethyl-3,5-dimethylene piperidinium chloride), poly (methyleneguanidine) hydrochloride, poly (ethylene imine) poly (ethylene imine) epichlorohydrin, poly (ethylene imine) ethoxylated, glutaraldehyde, and mixtures thereof; a catalyst; and a polymeric material capable of being crosslinked by the crosslinking agent and selected from the group consisting of polysaccharides having at least one hydroxy group, polysaccharides having at least one carboxy group, polysaccharides having at least one sulfate group, polysaccharides having at least one amine or amino group, polysaccharide gums, poly (alkylene oxides), vinyl polymers, and mixtures thereof; and a second coating in contact with the first coating which comprises a binder and a material selected from the group consisting of fatty imidazolines, ethosulfate quaternary compounds, dialkyl dimethyl methosulfate quaternary compounds, alkoxylated di-fatty quaternary compounds, amine oxides, amine ethoxylates, Imidazoline quaternary compounds, alkyl benzyl dimethyl quaternary compounds, poly (epiamines), and mixtures thereof.
U.S. Pat. No. 4,946,741 (Aono et al.) discloses an ink recording sheet comprising a transparent support having thereon an ink recording layer comprising a mixture of an amino group deactivated gelatin derivative and a polyalkylene oxide.
U.S. Pat. No. 4,781,985 (Desjarlais) discloses an ink jet transparency which comprises a substantially transparent resinous support and a substantially clear coating thereon which includes a specific fluorosurfactant.
U.S. Pat. No. 5,073,448 (Vieira et al.) discloses a recording material for ink jet printing comprising a carrier having a surface which can be printed on or a carrier coated on one side with a material which can be printed on, wherein the carrier or the coating contains as a stabilizer at least one compound of the formula ##STR6## in which R.sub.1 and R.sub.2 independently of one another are C.sub.1 -C.sub.4 alkyl which is unsubstituted or substituted by one or two --OH, --COO--M+ and/or --SO.sub.3.sup.- M+ groups, C.sub.3 -C.sub.5 alkenyl, C.sub.3 -C.sub.5 alkynyl, ##STR7## --CH.sub.2 CH(OH)CH.sub.2 --SO.sub.3 --M+, --CO-alkyl(C.sub.1 -C.sub.4) which is unsubstituted or substituted by --COOR.sup.o or --CO--N(R.sub.5)(R.sub.6) or, if OR.sub.1 and OR.sub.2 are in the ortho position relative to one another, R.sub.1 and R.sub.2 together are C.sub.1 -C.sub.6 alkylene, M+ being H+, a monovalent, divalent or trivalent metal cation or a group (R.sub.12 ')N+(R.sub.12 ")(R.sub.13 ')(R.sub.14 '), wherein R.sub.12 ', R.sub.12 ", R.sub.13 and R.sub.14 independently of one another are H, C.sub.1 -C.sub.4 alkyl which is unsubstituted or substituted by 1 or 3 OH, C.sub.1 -C.sub.4 alkyl interrupted by O, allyl, cyclopentyl, cyclohexyl, phenyl, benzyl or tolyl, or R.sub.1 is a group ##STR8## in which p' is a number from 2 to 6, R.sub.5 and R.sub.6 independently of one another are H or C.sub.1 -C.sub.4 alkyl which is unsubstituted or substituted by an OH, COOR.sup.o, --COO--M+, SO.sub.3 --M+, P(O)(O--M+).sub.2 or P(O)(OR.sup.o).sub.2 group, R.sub.3 ' and R.sub.4 ' independently of one another are H, C.sub.1 -C.sub.4 alkyl, OH or C.sub.1 -C.sub.4 alkoxy, R.sub.3 and R.sub.4 independently of one another are H, halogen, --OR.sub.7, --COOR.sup.o, --COO-M+, --OOC--R.sub.5, --CO--N(R.sub.5)(R.sub.6), --(R.sub.5)N--CO--R.sub.6, --CO--R.sub.5, --SO.sub.3 --M+, --SO.sub.2 N(R.sub.5)(R.sub.6), P(OR.sub.5).sub.3, --(O)P--(O--M+).sub.2, --(O)P--(OR.sup.o).sub.2, C.sub.1 -C.sub.8 alkyl which is unsubstituted or substituted by 1 to 7 --OR.sub.5 or --OO--C--R.sub.5 groups, by 1 or 2 --COOR.sup.o, --COO--M+, or --CO--N(R.sub.5)(R.sub.6) groups or by one or two --SO.sub.3 -M+, --SO.sub.2 N(R.sub.5)(R.sub.6) or --(O)P--(OR.sup.o).sub.2 or --(O)P(O--M+).sub.2 groups, where M+, R.sub.5 and R.sub.6 are as defined above, or C.sub.5 -C.sub.6 cycloalkyl or allyl, R.sup.o being C.sub.1 -C.sub.4 alkyl which is unsubstituted or substituted by an --OH group or --(CH.sub.2 CH.sub.2 O).sub.r --H in which r is 1 to 12, and R.sub.7 being C.sub.1 -C.sub.4 alkyl or --CO-alkyl(C.sub.1 -C.sub.4) each of which is unsubstituted or substituted by 1 or 2 --OH groups or R.sub.3 and R.sub.4 independently of one another are one of the groups ##STR9## in which R.sub.8 is a direct bond or methylene, R.sub.9 is H, C.sub.1 -C.sub.8 alkyl, --COO--M+ or --SO.sub.3 --M+, where M+, R.sub.1 and R.sub.2 are as defined above, R.sub.15 is --CO--, --(O).sub.g --C.sub.p H.sub.2p --CO--, --OOC--C.sub.p H.sub.2p --, --COO--C.sub.p H.sub.2p --, --O--CH.sub.2 CH(OH)--CH.sub.2 -- or ##STR10## in which g is 0 or 1 and p is 1 to 6 and R.sub.24 is --OR.sub.5, --N(R.sub.5)(R.sub.6) or a group ##STR11## and R.sub.16 is one of the following radicals: ##STR12## in which R.sub.25 is H or C.sub.1 -C.sub.4 alkyl, R.sub.17 is H, C.sub.1 -C.sub.4 alkyl which is unsubstituted or substituted by an --OH group, --CH.sub.2 --CH(OH)--CH.sub.2 --OH, C.sub.1 -C.sub.4 alkoxy, --OH, --CO-alkyl(C.sub.1 -C.sub.4), --COCH.dbd.CH.sub.2, allyl, benzyl or a group ##STR13## in which s is the number 2 or 3, t is a number from 0 to 2 and R.sub.21 and R.sub.22 independently of one another are H, C.sub.1 -C.sub.4 alkyl or phenyl.
South African Patent Application 924,610 discloses a transparent recording sheet suitable for making visual transparencies which comprises a thin transparent film backing bearing on at least one major surface thereof an ink jet receptive layer comprising from 1% to 10% of at least one acid having a pKa of from 2 to 6, said acid being selected from the group consisting of aryl monocarboxylic acids, aryloxy monocarboxylic acids, alkyl carboxylic acids having alkyl groups containing at least 11 carbon atoms, dicarboxylic acids, tricarboxylic acids, and pyridinium salts, and at least one liquid-absorbent polymer comprising from 90% to 99% aprotic constituents, wherein said sheet shows reduced fading when imaged with an ink containing triarylmethane dye and at least one nucleophile over an identical composition containing no protic organic-solvent-soluble additive.
U.S. Pat. No. 5,220,346 (Carreira et al.), the disclosure of which is totally incorporated herein by reference, discloses a printing process which comprises applying in imagewise fashion to a substrate an ink composition which comprises an aqueous liquid vehicle, a colorant, and an ionic compound at least partially ionizable in the liquid vehicle, said ink composition having a conductivity of at least about 10 milliSiemens per centimeter, and subsequently exposing the substrate to microwave radiation, thereby drying the images on the substrate. A specific embodiment of the invention is directed to a thermal ink jet printing process which comprises (1) incorporating into a thermal ink jet printing apparatus an ink composition which comprises an aqueous liquid vehicle, a colorant, and an ionic compound at least partially ionizable in the liquid vehicle, said ink composition having a conductivity of at least about 10 milliSiemens per centimeter; (2) heating the ink in an imagewise pattern to cause bubbles to form therein, thereby causing droplets of the ink to be ejected in an imagewise pattern onto a substrate, thereby generating images on the substrate; and (3) exposing the substrate to microwave radiation, thereby drying the images on the substrate.
Japanese Patent Publication JP 61-74880-A discloses a recording paper which contains (a) dimethyl diallylammonium chloride polymer; and (b) water soluble metal salt, such as CaF, LiCl, NaCl, KCl, RbCl, CrCl, KBr, LiI, Na.sub.2 SO.sub.4, K.sub.2 HPO.sub.3, K.sub.3 PO.sub.4, MgCl.sub.2, ZnCl.sub.2, MgCdSO.sub.4, or the like. The paper is used in ink jet recording, especially for multicolored recording, and is improved in preventing color tone difference due to the different printing order by each color ink while maintaining good water resistance.
U.S. Pat. No. 4,786,288 (Handa et al.), the disclosure of which is totally incorporated herein by reference, discloses an ink applying method for obtaining desired sharp patterns while preventing bleeding and an ink composition therefor, in applying a low viscosity liquid to a polymer product such as fabric in the form of droplets according to the ink jet or spray process. As a treating solution there is used a solution incorporating a water-soluble or water-dispersible material which contains --OSO.sub.3 M group or --SO.sub.3 M group as a hydrophilic group in which M is a monovalent metal, ammonium or amine, and a fiber structure is pretreated with a chemical for coagulating the said hydrophilic group, whereby good bleeding preventing effect and deep shading effect even against markedly bleeding fiber structures such as thin fabrics as well as level dyeing effect of colored portions can be attained without impairing the injection characteristic. Sharp patterns equal or superior to conventional prints can be obtained.
Copending application U.S. Ser. No. 08/034,917 (Attorney Docket No. D/92586), with the named inventors Shadi L. Malhotra, Brent S. Bryant, and Doris K. Weiss, filed Mar. 19, 1993, entitled "Recording Sheets Containing Phosphonium Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a base sheet, a phosphonium compound, an optional pigment, and an optional binder. In a preferred embodiment, the phosphonium compound is selected from the group consisting of ##STR14## wherein R is an alkyl group, X is an anion, and all four R groups are the same; ##STR15## wherein R is an alkyl group, wherein all three R groups are the same, wherein R is not the same as R', X is an anion, and R' is selected from the group consisting of alkyl groups, substituted alkyl groups, arylalkyl groups, and substituted arylalkyl groups; ##STR16## wherein Ar is an aryl group or a substituted aryl group, X is an anion, and all four Ar groups are the same; ##STR17## wherein Ar is an aryl group or a substituted aryl group, wherein all three Ar groups are the same, X is an anion, and R' is selected from the group consisting of alkyl groups, substituted alkyl groups, arylalkyl groups, and substituted arylalkyl groups; and mixtures thereof.
U.S. Pat. No. 5,314,747 (Malhotra et al.) the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises (a) a base sheet; (b) a cationic sulfur compound selected from the group consisting of sulfonium compounds, thiazolium compounds, benzothiazolium compounds, and mixtures thereof; (c) an optional binder; and (d) an optional pigment.
Copending application U.S. Ser. No. 08/033,917 (Attorney Docket No. D/92587), with the named inventors Shadi L. Malhotra and Brent S. Bryant, filed Mar. 19, 1993, entitled "Recording Sheets Containing Pyridinium Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a base sheet and a material selected from the group consisting of pyridinium compounds, piperazinium compounds, and mixtures thereof.
U.S. Pat. No. 5,320,902 (Malhotra et al.) the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which consists essentially of a substrate and, in contact with the substrate, a monoammonium compound of the formula: ##STR18## wherein R is an alkyl group, X is selected from the group consisting of fluoride, chloride, bromide, iodide, and astatide, and R', R", and R"' are each independently selected from the group consisting of alkyl groups, substituted alkyl groups, aryl groups, substituted aryl groups, arylalkyl groups, and substituted arylalkyl groups, wherein R, R', R" and R"' are either the same as or different from each other; and mixtures thereof; an optional binder component; and an optional filler component.
Copending application U.S. Ser. No. 08/033,918 (Attorney Docket No. D/92591), with the named inventors Shadi L. Malhotra, Brent S. Bryant, and Doris K. Weiss, filed Mar. 19, 1993, entitled "Recording Sheets Containing Tetrazolium, Indolinium, and Imidazolinium Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises (a) a base sheet; (b) a material selected from the group consisting of tetrazolium compounds, indolinium compounds, imidazolinium compounds, and mixtures thereof; (c) an optional pigment; and (d) an optional binder.
Copending application U.S. Ser. No. 08/196,922, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Alcohols and Saccharides," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of monosaccharides, oligosaccharides, and mixtures thereof. Another embodiment of the present invention is directed to a printing process which comprises (a) providing a recording sheet which comprises a substrate, a material selected from the group consisting of monomeric alcohols, monosaccharides, oligosaccharides, and mixtures thereof, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler; (b) applying an aqueous recording liquid to the recording sheet in an imagewise pattern; and (c) thereafter exposing the substrate to microwave radiation, thereby drying the recording liquid on the recording sheet.
Copending application U.S. Ser. No. 08/196,679, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Amino Acids, Hydroxy Acids, and Polycarboxyl Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a paper substrate and a material selected from the group consisting of monomeric amino acids, monomeric hydroxy acids, monomeric polycarboxyl compounds, and mixtures thereof. Another embodiment of the present invention is directed to a recording sheet which comprises a substrate and an additive material selected from the group consisting of monomeric amino acids, monomeric hydroxy acids, and mixtures thereof.
Copending application U.S. Ser. No. 08/196,607, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Amine Salts and Quaternary Choline Halides," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of monomeric amine acid salts, monomeric quaternary choline halides, and mixtures thereof.
Copending application U.S. Ser. No. 08,196,676, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Pyrrole, Pyrrolidine, Pyridine, Piperidine, Homopiperidine, Quinoline, Isoquinoline, Quinuclidine, Indole, and Indazole Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and an additive material selected from the group consisting of pyrrole compounds, pyrrolidine compounds, pyridine compounds, piperidine compounds, homopiperidine compounds, quinoline compounds, isoquinoline compounds, quinuclidine compounds, indole compounds, indazole compounds, and mixtures thereof.
Copending application U.S. Ser. No. 08/196,933, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Purine, Pyrimidine, Benzimidazole, Imidazolidine, Urazole, Pyrazole, Triazole, Benzotriazole, Tetrazole, and Pyrazine Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of purine compounds, pyrimidine compounds, benzimidazole compounds, imidazolidine compounds, urazole compounds, pyrazole compounds, triazole compounds, benzotriazole compounds, tetrazole compounds, pyrazine compounds, and mixtures thereof. Also disclosed is a recording sheet which consists essentially of a substrate, at least one material selected from the group consisting of purine compounds, pyrimidine compounds, benzimidazole compounds, imidazolidine compounds, urazole compounds, pyrazole compounds, triazole compounds, benzotriazole compounds, tetrazole compounds, pyrazine compounds, and mixtures thereof, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler.
Copending application U.S. Ser. No. 08/196,672, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Oxazole, Isooxazole, Oxazolidinone, Oxazoline Salt, Morpholine, Thiazole, Thiazolidine, Thiadiazole, and Phenothiazine Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of oxazole compounds, isooxazole compounds, oxazolidinone compounds, oxazoline salt compounds, morpholine compounds, thiazole compounds, thiazolidine compounds, thiadiazole compounds, phenothiazine compounds, and mixtures thereof. Also disclosed is a recording sheet which consists essentially of a substrate, at least one material selected from the group consisting of oxazole compounds, isooxazole compounds, oxazolidinone compounds, oxazoline salt compounds, morpholine compounds, thiazole compounds, thiazolidine compounds, thiadiazole compounds, phenothiazine compounds, and mixtures thereof, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler.
Copending application U.S. Ser. No. 08/196,605, with the named inventors Shadi L. Malhotra, Brent S. Bryant, and Arthur Y. Jones, filed concurrently herewith, entitled "Recording Sheets Containing Mildew Preventing Agents," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate, an image receiving coating, and a biocide.
While known compositions and processes are suitable for their intended purposes, a need remains for improved recording sheets. In addition, there is a need for improved recording sheets suitable for use in ink jet printing processes. Further, a need remains for recording sheets which exhibit rapid drying times when imaged with aqueous inks. Additionally, there is a need for recording sheets which enable precipitation of a dye from a liquid ink onto the sheet surface during printing processes. A need also remains for recording sheets which are particularly suitable for use in printing processes wherein the recorded substrates are imaged with liquid inks and dried by exposure to microwave radiation. Further, there is a need for recording sheets coated with a discontinuous, porous film. There is also a need for recording sheets which, subsequent to being imaged with an aqueous ink and dried by exposure to microwave radiation, exhibit little or no curling. In addition, there is a need for recording sheets suitable for use in thermal ink jet printing followed by exposure to microwave drying, wherein the imaged sheets exhibit increased solid area density. Further, a need exists for recording sheets suitable for use in thermal ink jet printing followed by exposure to microwave drying, wherein the imaged sheets exhibit improved resistance to showthrough. Additionally, there is a need for recording sheets suitable for use in thermal ink jet printing followed by exposure to microwave drying, wherein the imaged sheets exhibit reduced feathering. There is also a need for recording sheets suitable for use in thermal ink jet printing followed by exposure to microwave drying, wherein the imaged sheets exhibit intercolor bleed.